Core for making concrete culverts.



G. MILLER.

CORE FOR MAKING CONCRETE OULVERTS.

APPLICATION FILED NOV. 18. 1912.

Patented May 12, 1914.

wi/tweooao UNITED STATES PaTEN oFFroE.

GEORGE MILLER, OF FAIBFIELD, WASHINGTON; ASSIGNOR TO THE MILLER CONCRETE FORM COMPANY.

CORE FOR MAKING CCNCRETE CULVERTS.

Specification of Letters Patent. 7 I

Patented m 12, 1914.

Application filed November 18, 1912: Serial No. 731,988.

To all 10/10/11 it may concern:

Be it known that I, GEORGE MILLER, a citizen of the United States, residing at Fail-field. in the county of Spokane and State of \Yashington, have invented certain new and useful Improvements in Cores for Making Concrete Culverts, of which the following is a specification.

This invention relates to certain new and useful improvements in adjustable cores for making concreteculverts. i

It has for its object the provision of a simple, inexpensive and practical device of this character which is adapted to be readily adjusted to accommodate culverts of varying widths of arches.

"he invention consists in a novel construction hereinafter described and claimed.

Figure 1 a cross section ofa portion of -a culvert in perspective, with my adjustable core applied thereto. Fig. 2 is a cross sec-- tion of the culvert with a wider arch than that shown in Fig. 1, showing my invention applied thereto. Fig. 3 is a plan view of the side planks ofmy invent-ionshowing planks in the position taken when the core is about to be removed from culvert aft er casting. Fig. 4 is a perspective view of the extension bar used when a wide arch culvert is to be constructed.

In carrying out my invention I make use of arch rafters 10, supporting a web 11 of planking or metal as desired. The arch rafters are pivoted at 12 by} hinges 13, a strip of metal 15 being placed to cover the joint formed at the intersection of the webs 11 to render a perfectly smooth arch after the core has been withdrawn. The members 10 together with the web 11 rest upon side planking 16, which planking in turn rests upon sills 17. The planking 16 is constructed with a-beveled strip 18 attached at the bottom and resting on metal plate 19. 19 is supported by the sill member 17 which is constructed of timber with'a bevel face 20. positioned to be easily withdrawn from contact with the upper members of the core, and allowing them to drop away from the arch above. The planking 16 is supported outwardly by spreader bars 21 which are provided with a series of holes 22 to provide for adjustment and to be used in extending the core for a wider arch. The holes 22 are provided to receive pins 23 and be pivotal thereon. On the opposite end of bars 21 is provided a hole 24 for engagement with lnnge pins 25 securely fastened to the inside of the planking. A connecting bar 26 connects with the brace members 21 and with the pins '23 to render them movable and to displace the side members 16 when the core is to be removed from the culvert. A handle 27 is provided on the end of bar 26 to be within reach without the culvert, to cause a withdrawal of the core. Similar members 21. 25 and 26' are provided of substantially the same construction and designed to engage with the sill members 17 and to accomplish the withdrawal of the sills from the outer walls and from contact with the side wall members. When it is desired to construct a larger arch in a culvert than the core normally is adapted for an extension bar 28 is provided, the hinge pins in the hinges 12 may bewithdrawn and the bar inserted to provide the extension, bars of several sizes being a part of the core equipment to provide for various widths of arches. The under side of the extension bar 28 is provided with a metal plate 29 riveted at 30 to the extension bar and provided on its ends with a knife edge 31, said ends being slightly turned down to engage with the endsof rafter members 10 when in position. To cover up the opening in the web 11 thus provided by the extension bar a sheet metal strip 15 is used which will leave a perfect job when the core has been withdrawn, and which will serve to prevent any of the material from dropping through the form. All members as previously described are used in this wide arch construction but the pins 23 and 23 arewithdrawn and reinserted in the proper holes 22 and 22'-, to make the needed adjustment.

' W'hen the'core is set and ready for casting all parts are in the position shown in Fig. 1 and Fig. 2. After the culvert has been cast the cores may be removed by pulling outwardly 0n the handles 27 and 27, which will cause the members 21 and 21 to assume the position shown in Fig. 3 andwhich will draw toward the center of the culvert the sill 17 and the side planking 16, the handle 27' being first used allowin the sills to be entirely withdrawn from he culvert and the side planking to drop downward from engagement with the web supported by the rafters 10. The operation is then repeated for the side planking which will allow the no i arch consisting of members 10 and 11 to drop, their bottom edges closing slightly together by reason of the hinge 12 and allowing the arch members and the metal strip 15 to be withdrawn which will leave the culvert clear.

In extra long culverts it is my intention to construct a device in sections and in lengths that may be easily handled in connecting each section together with the bars 26 and 26 so that the removal of one section will cause the removal of all.

W hat I claim is- 1. A frame work for building sewers, conduits, etc.', comprising in combination, sills having outwardly and downwardly slanting upper faces, side members superimposed on said sills and'having outwardly and downwardly slanting beveled lower faces engaging the slanting faces of said sills, an arch supported on said side members, transversely disposed spreader bars pivotally connected with said sills and with each other, a longitudinally disposed operating bar nivoted to said s reader bars o spread or contract the same, and lever mechanism for spreading or contracting said side members, substantially as described.

2. A frame work for building sewers, conduits, etc., comprising in combination, side members supporting the sides of the sewer or conduit and having outwardly and downwardly beveled lower faces, an arch structure supported wholly by engagement of its base portions with and on said side members, sills having outwardly and downwardly slanting faces engaging the beveled faces of said members to elevate thelatter, adjustable means for contracting or spreading said side members, and adjustable means for spreading or contracting said sills, substantially as described.

3. A frame work for building sewers, conduits, etc., comprising in combination, lower side members having upper beveled faces and upper side members mounted on and having lower beveled faces engaging the upper beveled faces of the lower members, lever mechanism for spreading or separating the lower side members to elevate said upper side members, means for spreading the upper side members to support the sides of the sewer or conduit, and an arch structure supported wholly by engagement of its base portions with the tops of said upper side members, substantially as described.

in testimony whereof I affix my signature in presence of twowitnesses.

1 GEORGE MILLER.

\Vitnesses HAROLD E. SOANTLEBURY, PAUL B. VVARREN. 

